I need something fairly quiet, yet profitable to mine w/ power costs of $.09 - $.1/kwh. My office is a suite in a building that is kept very cool (as we have dentists w/ their required machinery, etc.), so heat isn't too much of an issue. My electric is a write-off, so I want a way to have a steady income of BTC whilst maintaining decent profitability (doesn't have to be the latest and greatest).
Maybe Scrypt ASICs are a possibility, but my focus at this moment is SHA256.
Thanks for your help/opinions!
Antminer S5 is probably the way to go. If you can buy a used one at around $350 and have cheap electricity, it's not too bad. You'll need to underclock it and put in a quieter fan though. I found the Delta's run quieter and am actually selling some extra ones.